Tubular cleaning up is a common procedure in situations such as after cementing but it also is used in other contexts. Most typically the tubular is casing and in applications where the size of the casing declines as the hole gets deeper. In those instances the scrapers typically comprise one or more rounded elements supported on a mandrel that is rotated either from the surface or with a downhole motor. The elements can be brushes that are spring biased outwardly against the tubular wall. The elements are supported from the mandrel against the torsional loads that occur during the scraping operation. Some examples of such scrapers are U.S. Pat. Nos. 6,343,648; 4,809,779; 6,152,221 and 6,484,802. Some designs involve linkages that extend opposed ends of scraping elements such as WO2001066907 to allow scraping of different size casing in the same trip. Also of general interest in the area of scrapers are US20060201670 and US20090313781 which illustrates a hand held scraper with a spring loaded blade.
Situations arise where the scraping needs to be done with a drill or production string in the borehole. In those instances the tool has to pass through a smaller dimension and then has to be deployed in significantly larger tubulars. In the past cutting tools that have pivotally mounted arms that are hydraulically extended have been used for descaling or scraping the interior wall of a surrounding larger tubular after being run in through a smaller tubular. These devices were modified tubular cutters where the same pivoting blades were used but different end treatments were applied to accomplish the objective of cleaning or descaling rather than cutting through the tubular. It was determined that such modified blades fitted on line cutting tool bodies were marginally effective for cleaning or descaling. The reason was that there was very limited contact are at the cantilevered ends of the blades to accomplish that function. The present invention seeks to improve the cleaning ability of such a tool and addresses the issue with an articulated lower end for the blades so that when the blades are extended to a preferred angle of about 45 degrees, although other angles are contemplated, the lower ends are articulated into a near parallel orientation to the tubular wall so that the contact area is enhanced as the tool cleans while being rotated. The envisioned tool has other applications such as for honing the inside wall of a tubular, milling or cleaning around objects in the tubular in a direction moving toward the tubular axis or using the tool as a latch tool to anchor itself or attached tools or to move other tools within the tubular. These and other aspects of the present invention will be more readily apparent to those skilled in the art from a review of the description of the preferred embodiment and the associated drawings while recognizing that the full scope of the invention is to be determined from the appended claims.